See once we have written /*.. anything after that will be marked as comment be it in the same or different line.. since x=/* exam is enclosed within the blue and green coloured /* ,*/ so they we will be treated as part of the comment.
Comments here are indicated by blue color.
In the first main() once we have ended the comment using */ from the very next character it is out of the comment zone.
While in the 2nd main() i have not given */ so there is no end to the comment. Everything is in blue after /*.